78049889 has 2 divisors, whose sum is σ = 78049890. Its totient is φ = 78049888.

The previous prime is 78049843. The next prime is 78049901. The reversal of 78049889 is 98894087.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 46689889 + 31360000 = 6833^2 + 5600^2 .

It is a cyclic number.

It is not a de Polignac number, because 78049889 - 2¹⁶ = 77984353 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 78049889.

It is not a weakly prime, because it can be changed into another prime (78049819) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39024944 + 39024945.

It is an arithmetic number, because the mean of its divisors is an integer number (39024945).

Almost surely, 2^78049889 is an apocalyptic number.

It is an amenable number.

78049889 is a deficient number, since it is larger than the sum of its proper divisors (1).

78049889 is an equidigital number, since it uses as much as digits as its factorization.

78049889 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1161216, while the sum is 53.

The square root of 78049889 is about 8834.5848232953. The cubic root of 78049889 is about 427.3569422038.

The spelling of 78049889 in words is "seventy-eight million, forty-nine thousand, eight hundred eighty-nine".